1. Field of the Invention
The present invention relates to a delivery valve that includes a housing in the form of a cylindrical sleeve having valve slots that extend in a circumferential direction and in front of which are disposed cylindrically bent valve tongues or reeds that, in an opening position, rest against travel-receivers in an elliptically bent configuration The sleeve is disposed in a wall portion of a rotary piston compressor for gaseous medium, the sleeve being disposed in the wall portion in a bore thereof that extends parallel to the shaft axis of the compressor. The bore communicates with a respective delivery chamber of the compressor via delivery ports in the compressor wall portion, and in a radial direction communicating on at least one side with a delivery line.
2. Description of the Prior Art
A delivery valve of this general type is disclosed in German Offenlegungsschrift No. 33 07 856 Eiermann dated Sept. 6, 1984, belonging to the assignee of the present invention and is described in principle in U.S. Pat. No. 4,149,834 Eiermann et al dated Apr. 17, 1979.
With the great length of the valve reeds of such an arrangement, and the freely pivotable ends thereof, the necessary bending stresses during opening of the valve are distributed over the entire length expansion of the valve reeds, and as a result of this low stress, a high operational reliability and a long service life are achieved.
However, in the construction disclosed in German Offenlegungsschrift No. 33 07 856 Eiermann, the gases that discharge radially when the valve is opened have a restricted path for passing from the valve slots in the axial direction on the one hand, and laterally about the valve reeds and the space between the individual travel-receivers to the lateral outlet or outlets of the valve. As a result, and due to the turbulence generated thereby, pressure increases and flow resistance results in the discharged gases.
It is therefore an object of the present invention to avoid these drawbacks by expanding the flow paths of the pressurized gases through the delivery valve with structurally easy to manufacture measures.